Put rhe vebs in bracket in the correct form(past simple or

Put rhe vebs in bracket in the correct form(past simple or past continuous tense).
1.When I came home my mom ... dinner for us.(to cook)
2."What ... you ... about?" (to talk)- "Nothing serious".
3.I am sorry I couldn"t join you yestarday. I ... for my exam.(to prepare)
4. What ...you... at a minute ago?(to laugh)-It was the funniest joke I"ve ever heard.
5. The spaceship captain ... the satellite which ... very fast. (to notice/to move) It was dangerous!